Copper and Copper alloys, considered the high electrical conductivity combined with the reduced resistance, make the copper parts, practically not weldable in resistance, if not using technical devices.
The main precaution is to resort to a transfer of the contact resistance, using resistance welding electrodes with refractory material such as Tungsten or Molybdenum.
In this way the greater resistance, due to the contact of these high-strength refractory materials, is transferred from the contact of the inner surfaces of the pieces to be welded, to the contact between the electrode tips and the external surfaces of the parts.
The heat transfer will then take place, from the outside to the inside, with the consequence that fused core, compared to that of ferrous metals, will have a smaller diameter but a more important thickness with a deeper hole in the electrode.
A.T.S. is a qualified supplier of the main copper alloy resistance welding electrodes with Tungsten or Molybdenum insert.